New dynamic bandwidth allocation algorithm analysis: DDSPON for ethernet passive optical networks

This project aims to present the state of the art in Dynamic Bandwidth Allocation (DBA) solutions, as well as the study and evaluation of one proposal of DBA algorithm: the Distributed Dynamic Scheduling for EPON (DDSPON), which is the UPC contribution to the research in scheduling algorithms for EPON

CSMA/CA using pilot tone on PON

Jorden Yeong-Tswen, Tse.Thesis (M.Phil.)--Chinese University of Hong Kong, 2003.Includes bibliographical references (leaves 76-76).Abstracts in English and Chinese.ACKNOWLEDGEMENTS --- p.2ABSTRACT --- p.3摘要 --- p.4CONTENTS --- p.5Chapter CHAPTER 1: --- INTRODUCTION --- p.8Chapter 1.1. --- First Mile Evolution --- p.8Chapter 1.2. --- Access： Passive Optical Network (PON) --- p.10Chapter 1.2.1. --- ATM-PON (APON) --- p.13Chapter 1.2.2. --- Ethernet PON (EPON) --- p.14Chapter 1.3. --- Problem Definition and Possible Solutions --- p.16Chapter 1.3.1. --- Wavelength Division Multiplexing (WDM) --- p.17Chapter 1.3.2. --- Time Division Multiplexing (TDM) --- p.18Chapter 1.3.3. --- Sub-carrier Multiplexing (SCM) & Frequency Division Multiplexing (FDM) --- p.20Chapter 1.3.4. --- Code Division Multi Access (CDMA) --- p.20Chapter 1.4. --- Thesis Organization --- p.20Chapter CHAPTER 2: --- BACKGROUND --- p.22Chapter 2.1. --- EPON Solution：- MPCP --- p.22Chapter 2.2. --- CSMA/CD on PON --- p.26Chapter 2.3. --- Motivation --- p.28Chapter CHAPTER 3: --- CSMA/CA PROTOCOL USING PILOT TONE ON PON --- p.29Chapter 3.1. --- Basic Protocol Description --- p.29Chapter 3.1.1. --- With No Contention --- p.31Chapter 3.1.2. --- With Contention --- p.32Chapter 3.1.3. --- With Contention and Winner --- p.33Chapter 3.2. --- Simulation --- p.35Chapter 3.2.1. --- Effect of Loading on Network Utilization --- p.37Chapter 3.2.2. --- Effect of Network Size on Utilization --- p.39Chapter 3.2.3. --- Delay Performance --- p.41Chapter 3.2.4. --- Effect of Distance from Remote Node --- p.44Chapter 3.2.5. --- Effect of Maximum Packet Duration on Utilization and Delay --- p.45Chapter 3.3. --- Conclusions --- p.47Chapter CHAPTER 4: --- PROTOCOL ENHANCEMENT ON VARIOUS ASPECTS --- p.48Chapter 4.1. --- Utilization Enhancement --- p.48Chapter 4.1.1. --- Improvement on Network Utilization --- p.50Chapter 4.1.2. --- Network Delay Performance --- p.52Chapter 4.1.3. --- Conclusions --- p.53Chapter 4.2. --- Capture Effect --- p.53Chapter 4.2.1. --- Solution by Varying Ts --- p.54Chapter 4.2.2. --- Simulations --- p.55Chapter 4.2.3. --- Conclusions --- p.58Chapter 4.3. --- Introducing Cos to existing network --- p.59Chapter 4.3.1. --- Principle --- p.59Chapter 4.3.2. --- Simulation Model --- p.60Chapter 4.3.3. --- Utilization Performance --- p.61Chapter 4.3.4. --- Delay Performance --- p.64Chapter 4.3.5. --- Conclusions --- p.68Chapter CHAPTER 5: --- CONCLUSIONS --- p.69Chapter 5.1. --- Thesis Summary --- p.69Chapter 5.2. --- Future Work --- p.71REFERENCES --- p.7

Multichannel optical access networks : design and resource management

At present there is a strong worldwide push towards bringing fiber closer to individual homes and businesses. The next evolutionary step is the cost-effective all-optical integration of fiber-based access and metro networks. STARGATE [1] is an all-optical access-metro architecture which does not rely on costly active devices, e.g., Optical Cross-Connects (OXCs) or Fixed Wavelength Converters (FWCs), and allow low-cost PON technologies to follow low-cost Ethernet technologies from EPON access into metro networks, resulting in significantly reduced cost and complexity. It makes use of an overlay island of transparency with optical bypassing capabilities. In this thesis we first propose Optical Network Unit (ONU) architectures, and discuss several technical challenges, which allow STARGATE EPONs (SG-EPONs) to evolve in a pay-as-you-grow manner while providing backward compatibility with legacy infrastructure and protecting previous investment. Second, and considering all the hardware constraints, we present the corresponding dynamic bandwidth allocation algorithm for effective resource management in these networks and investigate their performances (delay, throughput) through simulation experiments. We further investigate the problem of transmission grant scheduling in multichannel optical access networks using a scheduling theoretic approach. We show that the problem can be modeled as an Open Shop and we formulate the joint scheduling and wavelength assignment problem as a Mixed Integer Linear Program (MJLP) whose objective is to reduce the length of a scheduling period. Since the problem is known to be NP-hard, we introduce a Tabu Search based heuristic for solving the joint problem. Different other heuristics are also considered and their performances are compared with those of Tabu and MILP. Results indicate that by appropriately scheduling transmission grants and assigning wavelengths, substantial and consistent improvements may be obtained in the network performance. For example, Tabu shows a reduction of up to 29% in the schedule length with substantial reduction in channel idle gaps yielding to both higher channel utilization and lower queuing delays. Additionally, when the number of channels in the network is not small, the benefits of performing appropriate wavelength assignment, together with transmission scheduling, are observed and discussed. We further perform a packet-level simulation on the considered network to study the benefits of efficient grant scheduling; significant improvements are shown both in terms of system utilization and packet queuing delays

Allocation des ressources et des solutions pour économiser de l'énergie dans les réseaux optiques d'accès

In this thesis, general overview about PON systems is presented and existing PON mechanisms and classification are investigated. After, a novel dynamic bandwidth allocation algorithm for EPON is introduced. This proposed algorithm is named as “Half Cycling Dynamic Bandwidth Allocation-hcDBA” by the inspiration of its half cycling processing mode. Later, an improvement of hcDBA algorithm with early prediction mechanism is presented. As a result statement of the study, hcDBA algorithm performs better than existing mechanism in terms of packet loss ratio and access delays. Beside, simulation traffic behavior of EPON’s upstream channel has been investigated in order to support the decision of selecting suitable traffic generator in further studies. Energy conversation is one of the hot topics in telecommunication networks. Access networks constitute remarkable portion of the total energy consumption in telecommunication networks. ITU-T and IEEE organizations published recommendation for energy conversation in PONs. While, total energy consumption of ONUs is more than other equipment in fix access network the standards and most of the researches focused on saving energy at ONU side. In this thesis I focused on an energy efficiency method based on energy conversation on OLT side. The proposed method save energy by dynamically moving OLT cards to deep sleep mode according to the incoming and outgoing traffic loadsDans ce travail de thèse, un aperçu général sur les systèmes PON est présenté et sont étudiés les mécanismes et classification PON existants. Après, nous introduisons notre première contribution qui est un algorithme d'allocation dynamique de bande passante pour EPON. Cet algorithme proposé est désigné comme «hcDBA». Par la suite, une amélioration de l'algorithme de hcDBA avec mécanisme de prédiction précoce est présentée. Notre simulation montre bien que notre algorithme hcDBA est performant comparé aux mécanismes existants en termes de taux de perte de paquets et de délai d’accès. Dans notre seconde contribution, nous sommes intéressés au problème de consommation d’énergie qui est un sujet d’actualité dans les réseaux de télécommunication. Les études montrent aujourd’hui que les réseaux d'accès constituent une partie remarquable de la consommation totale d'énergie dans les réseaux de télécommunication. Les organisations ITU-T et IEEE ont publié la recommandation pour la conversation de l'énergie pour les réseaux PONs. Bien que, la consommation totale d'énergie des nœuds ONU est plus importantes que d'autres équipements dans le réseau d'accès fixe, les normes et la plupart des travaux de recherches ont porté sur les économies d'énergie du côté de ONU. Dans cette thèse, nous sommes concentrés sur une méthode d'efficacité énergétique basée sur la conservation de l'énergie du côté de l’OLT. La méthode proposée permet d’économiser de l'énergie en déplaçant dynamiquement des cartes d’OLT en mode de sommeil profond en fonction des charges de trafic entrant et sortan

Dynamic bandwidth management with service differentiation over ethernet passive optical networks

Ethernet passive optical networks (EPONs) address the first mile of the communication infrastructure between the service provider central offices and the customer sites. As a low-cost, high speed technology, EPONs are deemed as the solution to the bottleneck problem of the broadband access network. A major feature of EPONs is the utility of a shared upstream channel among the end users. Only a single optical network unit (GNU) may transmit during a timeslot to avoid data collisions. In order to provide diverse quality of service (QoS), the bandwidth management of the upstream channel is essential for the successful implementation of EPONs, and thus, an efficient medium access control is required to facilitate statistical multiplexing among local traffics. This dissertation addresses the upstream bandwidth allocation over EPONs. An efficient mechanism, i.e., limited sharing with traffic prediction (LSTP), has been proposed to arbitrate the upstream bandwidth among ONUs. The MultiPoint Control Protocol (MPCP) messages, which are stipulated by the IEEE 802.3ah Ethernet in the First Mile (EFM) Task Force, are adopted by LSTP to facilitate the dynamic bandwidth negotiation between an GNU and the OLT. The bandwidth requirement of an ONU includes the already enqueued frames and the predicted incoming frames during the waiting time. The OLT arbitrates the bandwidth assignment based on the queue status report from an GNU, the traffic prediction, and the agreed service contract. With respect to the performance evaluation, theoretical analysis on the frame loss, the frame delay, and the queue length has been conducted. The quantitative results demonstrate that 1) the innovative LSTP mechanism dynamically allocates the upstream bandwidth among multiple ONUs; 2) the traffic predictor at the OLT delivers satisfactory prediction for the bursty self-similar traffic, and thereby, contributing to the reduction of frame loss, frame delay, and queue length; and 3) the bandwidth arbitration at the OLT effectively restricts the aggressive bandwidth competition among ONUs by adopting the service level agreement (SLA) parameter as the upper bound. Aside from analysis, the LSTP mechanism has been substantiated by experimental simulations. In order to differentiate the service provisioning among diverse users, LSTP is further enhanced with the support of dynamic bandwidth negotiation based on multiple queues. The incoming traffics are first classified into three classes, and then enqueued into the corresponding queues. A traffic predictor is dedicated to one class of traffic from an GNU. Service differentiation among classes are provided by the combination of queuing and scheduling at the GNU side. At the OLT side, the bandwidth allocation for each class of traffic is based on the reported queue status and the traffic prediction, and is upper-bounded by the SLA parameter. Experimental simulations have justified the feasibility of providing service differentiation over the broadband EPONs

Design and Performance Analysis of Functional Split in Virtualized Access Networks

abstract: Emerging modular cable network architectures distribute some cable headend functions to remote nodes that are located close to the broadcast cable links reaching the cable modems (CMs) in the subscriber homes and businesses. In the Remote- PHY (R-PHY) architecture, a Remote PHY Device (RPD) conducts the physical layer processing for the analog cable transmissions, while the headend runs the DOCSIS medium access control (MAC) for the upstream transmissions of the distributed CMs over the shared cable link. In contrast, in the Remote MACPHY (R-MACPHY) ar- chitecture, a Remote MACPHY Device (RMD) conducts both the physical and MAC layer processing. The dissertation objective is to conduct a comprehensive perfor- mance comparison of the R-PHY and R-MACPHY architectures. Also, development of analytical delay models for the polling-based MAC with Gated bandwidth alloca- tion of Poisson traffic in the R-PHY and R-MACPHY architectures and conducting extensive simulations to assess the accuracy of the analytical model and to evaluate the delay-throughput performance of the R-PHY and R-MACPHY architectures for a wide range of deployment and operating scenarios. Performance evaluations ex- tend to the use of Ethernet Passive Optical Network (EPON) as transport network between remote nodes and headend. The results show that for long CIN distances above 100 miles, the R-MACPHY architecture achieves significantly shorter mean up- stream packet delays than the R-PHY architecture, especially for bursty traffic. The extensive comparative R-PHY and R-MACPHY comparative evaluation can serve as a basis for the planning of modular broadcast cable based access networks.Dissertation/ThesisDoctoral Dissertation Electrical Engineering 201

On the Merits of Deploying TDM-based Next-Generation PON Solutions in the Access Arena As Multiservice, All Packet-Based 4G Mobile Backhaul RAN Architecture

The phenomenal growth of mobile backhaul capacity required to support the emerging fourth-generation (4G) traffic including mobile WiMAX, cellular Long-Term Evolution (LTE), and LTE-Advanced (LTE-A) requires rapid migration from today\u27s legacy circuit switched T1/E1 wireline and microwave backhaul technologies to a new fiber-supported, all-packet-based mobile backhaul infrastructure. Clearly, a cost effective fiber supported all-packet-based mobile backhaul radio access network (RAN) architecture that is compatible with these inherently distributed 4G RAN architectures is needed to efficiently scale current mobile backhaul networks. However, deploying a green fiber-based mobile backhaul infrastructure is a costly proposition mainly due to the significant cost associated with digging the trenches in which the fiber is to be laid. These, along with the inevitable trend towards all-IP/Ethernet transport protocols and packet switched networks, have prompted many carriers around the world to consider the potential of utilizing the existing fiber-based Passive Optical Network (PON) access infrastructure as an all-packet-based converged fixed-mobile optical access networking transport architecture to backhaul both mobile and typical wireline traffic. Passive Optical Network (PON)-based fiber-to-the-curb/home (FTTC/FTTH) access networks are being deployed around the globe based on two Time-Division Multiplexed (TDM) standards: ITU G.984 Gigabit PON (GPON) and IEEE 802.ah Ethernet PON (EPON). A PON connects a group of Optical Network Units (ONUs) located at the subscriber premises to an Optical Line Terminal (OLT) located at the service provider\u27s facility. It is the purpose of this thesis to examine the technological requirements and assess the performance analysis and feasibility for deploying TDM-based next-generation (NG) PON solutions in the access arena as multiservice, all packet-based 4G mobile backhaul RAN and/or converged fixed-mobile optical networking architecture. Specifically, this work proposes and devises a simple and cost-effective 10G-EPON-based 4G mobile backhaul RAN architecture that efficiently transports and supports a wide range of existing and emerging fixed-mobile advanced multimedia applications and services along with the diverse quality of service (QoS), rate, and reliability requirements set by these services. The techno-economics merits of utilizing PON-based 4G RAN architecture versus that of traditional 4G (mobile WiMAX and LTE) RAN will be thoroughly examine and quantified. To achieve our objective, we utilize the existing fiber-based PON access infrastructure with novel ring-based distribution access network and wireless-enabled OLT and ONUs as the multiservice packet-based 4G mobile backhaul RAN infrastructure. Specifically, to simplify the implementation of such a complex undertaking, this work is divided into two sequential phases. In the first phase, we examine and quantify the overall performance of the standalone ring-based 10G-EPON architecture (just the wireline part without overlaying/incorporating the wireless part (4G RAN)) via modeling and simulations. We then assemble the basic building blocks, components, and sub-systems required to build up a proof-of-concept prototype testbed for the standalone ring-based EPON architecture. The testbed will be used to verify and demonstrate the performance of the standalone architecture, specifically, in terms of power budget, scalability, and reach. In the second phase, we develop an integrated framework for the efficient interworking between the two wireline PON and 4G mobile access technologies, particularly, in terms of unified network control and management (NCM) operations. Specifically, we address the key technical challenges associated with tailoring a typically centralized PON-based access architecture to interwork with and support a distributed 4G RAN architecture and associated radio NCM operations. This is achieved via introducing and developing several salient-networking innovations that collectively enable the standalone EPON architecture to support a fully distributed 4G mobile backhaul RAN and/or a truly unified NG-PON-4G access networking architecture. These include a fully distributed control plane that enables intercommunication among the access nodes (ONUs/BSs) as well as signaling, scheduling algorithms, and handoff procedures that operate in a distributed manner. Overall, the proposed NG-PON architecture constitutes a complete networking paradigm shift from the typically centralized PON\u27s architecture and OLT-based NCM operations to a new disruptive fully distributed PON\u27s architecture and NCM operations in which all the typically centralized OLT-based PON\u27s NCM operations are migrated to and independently implemented by the access nodes (ONUs) in a distributed manner. This requires migrating most of the typically centralized wireline and radio control and user-plane functionalities such as dynamic bandwidth allocation (DBA), queue management and packet scheduling, handover control, radio resource management, admission control, etc., typically implemented in today\u27s OLT/RNC, to the access nodes (ONUs/4G BSs). It is shown that the overall performance of the proposed EPON-based 4G backhaul including both the RAN and Mobile Packet Core (MPC) {Evolved Packet Core (EPC) per 3GPP LTE\u27s standard} is significantly augmented compared to that of the typical 4G RAN, specifically, in terms of handoff capability, signaling overhead, overall network throughput and latency, and QoS support. Furthermore, the proposed architecture enables redistributing some of the intelligence and NCM operations currently centralized in the MPC platform out into the access nodes of the mobile RAN. Specifically, as this work will show, it enables offloading sizable fraction of the mobile signaling as well as actual local upstream traffic transport and processing (LTE bearers switch/set-up, retain, and tear-down and associated signaling commands from the BSs to the EPC and vice-versa) from the EPC to the access nodes (ONUs/BSs). This has a significant impact on the performance of the EPC. First, it frees up a sizable fraction of the badly needed network resources as well as processing on the overloaded centralized serving nodes (AGW) in the MPC. Second, it frees up capacity and sessions on the typically congested mobile backhaul from the BSs to the EPC and vice-versa